Deck VIII Flashcards Preview

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Flashcards in Deck VIII Deck (30):

What complication is characteristic of a hemodynamically significant atrial septal defect?

Pulmonary hypertension which may cause Eisenmenger syndrome (reversal of shunting).


What do Langerhan's cells look like histologically?

Multiple nuclei peripherally organized in the shape of a horseshoe.


What condition are Langerhan's cells characteristic of?

Granulomatous conditions.


What reflex is mediated by the superior laryngeal nerve (CN X)?

Cough reflex.


Name two structures that would likely be injured in a very deep stab wound to the left, 5th intercostal space at the midclavicular line.

Left lung; apex of the heart (L. ventricle)


What would you expect the results of a nasal transepithelial potential difference test to be in a patient with CF?

More negative nasoepithelial surface due to increased luminal sodium absorption.


What ion imbalances are characteristic of a defective CFTR protein?

Reduced epithelial chloride secretion causing an indirect increase in sodium absorption


Describe changes in respiratory tidal volume in a patient with Cheyne-Stokes respirations.

Cyclic breathing in which apnea is followed by gradually increasing tidal volumes and then gradually decreasing tidal volumes until the next apneic period.


In what conditions are Cheyne-Stokes respirations seen?

advanced CHF, neurologic disease (stroke, brain tumors, TBI)


What is the pathophysiology associated with symptomatic panic attacks?

Hyperventillation causes decreased pCO2. Hypocapnia causes cerebral vasoconstriction and decreased cerebral blood flow leading to dizziness, weakness, and blurred vision.


Which types of immune response cells contribute to containing an M. Tuberculosis infection within a caseous granuloma?

CD4+ TH1 lymphocytes and macrophages.


In a patient with CHF and fluid in the pulmonary interstitium, what would be the acute cause of dyspnea?

Decreased lung compliance due to fluid buildup.


How are most inhaled particles lodged in the bronchial tree removed from the lungs?

Via proximal transport of mucus by ciliated epithelial cells (mucocilliary clearance)


Where are goblet cells found?

Only in the trachea and larger bronchioles.


Name two factors that are released during anaphylaxis from widespread mast cell degranulation.

Histamine and Tryptase.


How is degranulation of mast cells initiated?

Crosslinking of multiple membrane-bound IgE antibodies by a specific antigen resulting in an aggregation of IgE-Fc receptors on mast cell surfaces.


In a patient with restrictive lung disease, what may cause expiratory flow rates to be increased?

Decreased lung compliance (increased elastic recoil) and increased radial traction is exerted on the conducting airways by the fibrotic lung.


What protein is released by eosinophils to kill helminths?

Major Basic Protein.


What finding would you expect in a patient with COPD and longstanding hypercapnea?

Cerebral vasodilation via decreased cerebral vascular resistance to compensate for hypoxia.


At what point in the breathing cycle is pulmonary vascular resistance lowest?

At the functional residual capacity.


How are large particles (10-15 um) cleared by the respiratory tract?

Trapped in the upper respiratory tract.


How are medium sized particles (2.5-10um) cleared by the respiratory tract?

Mucocilliary transport.


How are fine particles (less than 2 um) cleared by the respiratory tract?

They reach the terminal bronchi and alveoli and are phagocytosed by macrophages.


What is the most common site of obstruction causing fetal hydronephrosis?

Ureteropelvic junction.


What are the earliest disease manifestations of Fabry's disease?

Hypohidrosis (diminished sweating), acroparesthesia (neuropathic pain of the extremities), aniokeratomas (dark, punctuate non blanching red macules and papules usually located between the umbilicus and knees


Where along the nephron is the most likely site for uric acid precipitation and why?

Uric acid precipitates in an acidic environment; therefore it most often precipitates in the distal tubules and collecting ducts where pH is lowest.


What treatments may reduce the risk of tumor lysis syndrome?

Urine alkalinization, hydration.


What is a variocele?

A mass of varicose veins in the spermatic cord.


What symptom may occur in a male with a left sided renal vein obstruction?

Left sided varicocele; left gonadal vein drains right into the left renal vein (right gonadal vein drains directly into the IVC)


In rapidly progressive glomerurlonephritis, what type of deposition is essential to crescent formation?

Fibrin deposition